<PRE><B>Question 1107789</B>
&lt;br&gt;
The responses from the other tutors show solutions using an equation that says the distances the two directions are the same.&lt;br&gt;
A different setup makes the algebra needed to solve the problem easier.&lt;br&gt;
Since the distances are the same and the time returning is half the time going, the speed returning is twice the speed going.&lt;br&gt;
Let the boat speed by x; then the speed going is x-6 and the speed returning is x+6:&lt;br&gt;
{{{x+6=2(x-6)}}}
{{{x+6=2x-12}}}
{{{18=x}}}&lt;br&gt;
ANSWER: 18 km/hr&lt;br&gt;
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